Match the following: Column I Column II A Mutation breeding 1 Laborious and expensive process to obtain gene variation B Selection 2 Hybrid vigour can be maintained for several generations C Hybridisation 3 Simplest and easiest method of plant improvement D Introduction 4 Oldest breeding method 5 Quick method to obtain gene variation

Answer

To solve the matching question, we will analyze each term in Column I and find the corresponding description in Column II.

### Step-by-Step Solution:

1. **Mutation Breeding (A)**:
- Mutation breeding is a method that involves inducing mutations in plants to create new varieties. This is typically done using radiation (like X-rays or UV light).
- It is known for being a **quick method to obtain gene variation**.
- **Match**: A - 5

2. **Selection (B)**:
- Selection is the oldest method of plant breeding, where plants with desirable traits are chosen for reproduction.
- It serves as the foundation for all crop improvement programs.
- **Match**: B - 4

3. **Hybridisation (C)**:
- Hybridisation involves the interbreeding of individuals from different species or genetically divergent individuals.
- This process can be labor-intensive and expensive, as it may produce offspring that are fertile, partially fertile, or sterile.
- **Match**: C - 1

4. **Introduction (D)**:
- Introduction refers to the process of importing better varieties of plants from outside sources and integrating them into the local environment.
- This method is considered the simplest and easiest way to improve plant varieties.
- **Match**: D - 3

### Final Matches:
- A - 5 (Mutation breeding: Quick method to obtain gene variation)
- B - 4 (Selection: Oldest breeding method)
- C - 1 (Hybridisation: Laborious and expensive process to obtain gene variation)
- D - 3 (Introduction: Simplest and easiest method of plant improvement)

### Summary of Matches:
- A → 5
- B → 4
- C → 1
- D → 3